Cellular communications systems are widely used for providing wireless voice communications between mobile cellular telephones and base stations. More particularly, when a cellular phone is turned on it establishes communications with a base station, which informs a central switching station that calls for the cellular phone are to be routed through that particular base station. The base stations and the central switching station may communicate via a dedicated fiber optic or optical communications link, for example.
As technology continues to improve, cellular telephones are capable of performing an increasing number of functions for users. For example, many cellular telephone devices now incorporate the functionality of personal data assistant (PDA) devices, such as calendars, address books, etc. Moreover, these types of devices also allow users to send and retrieve electronic mail (email) via the cellular communications system. Indeed, many mobile cellular communications devices now have processing and storage capabilities that a few years ago were only available in personal computers (PCs).
The communications infrastructure connecting central switching stations and base stations is typically capable of facilitating large amounts of data transfer therebetween. However, the capacity of base stations for wireless data communications is much more limited. As such, users are typically charged by the amount of airtime they use, so it is usually not feasible to transfer relatively large amounts of data in this manner. Thus, the functionality of multi-function cellular devices is still somewhat restricted with respect to the data they can access wirelessly via a base station.
Various approaches have been proposed to manage communications traffic over, and therefore better utilize, wireless cellular communication links. By way of example, U.S. Pat. No. 5,742,588 discloses a method and system of packet switched traffic management in a cellular telecommunications system. A packet switched radio channel (PRCH) manager is used for each cell of a cellular system, and a PRCH controller is used for each PRCH in the cell. A PRCH manager interacts with and controls one or more PRCH controllers. The PRCH manager evaluates service requests, handles a PRCH admission queue, and manages the active PRCHs of the cell. The PRCH controllers supervise ongoing traffic, control admission, and control traffic congestion for each individual PRCH. A system operator sets a maximum tolerable delay for each PRCH and a priority for each packet call.
While such traffic management approaches may provide improved performance, attempting to simultaneously use the limited wireless capacity of base stations for very large data transfers and voice communications may still cause traffic management problems.